1. Field of the Invention
This invention relates to windshield washer pumps used in vehicles, and more particularly, to a windshield washer impeller and impeller housing which cooperate to reduce or eliminate vibration in the washer pump.
2. Description of the Related Art
In the field of vehicle washer pumps that are centrifugal in their design, a rigid impeller is situated inside a pump cavity that creates a pressure from a pump inlet to a pump outlet in order to pump a windshield washer fluid therebetween. The impeller is typically driven by a washer motor to create the pumping action.
It was not uncommon that the impellers had an elongated nose or end that extended into an inlet area of the pump cavity in order to "prime" the pump with a minimum amount of washer fluid in the event a reservoir of washing fluid was pumped until it was empty and then re-filled which caused air pocket to be created in the pump cavity. The elongated nose or end of the impeller caused washer fluid in the re-filled reservoir to become agitated, thereby displacing the air pocket in the pump cavity. The air pocket in the pump cavity would often cause noise and vibration which may, in turn, damage the parts of the pump.
Unfortunately, one of the problems with using an impeller having an elongated end was that the impeller had a tendency to "walk" or "track" an inner surface of the impeller housing. This, in turn, resulted in noise and vibration and, sometimes, even damaged components of the pump.
What is needed, therefore, is a simplistic and relatively inexpensive system and method to reduce or eliminate this noise and vibration and to provide an improved pump design.